![]() The Early Cenozoic Era: Enter The Megalodonĭuring the Cenozoic period, about 60 million years ago, the most famous prehistoric shark evolved, one that defined sharks as a ruthless, efficient, apex predators: The Megalodon. Lamnidae are the predecessors of modern sharks like Great Whites, Mako Sharks, and Bull Sharks. The Cretaceous was also the time period when Lamnidae Sharks, sometimes referred to as white sharks, with the anatomy of what we think of sharks having today, evolved. Filter feeders like the Whale Shark, the Basking Shark, and the megamouth shark first appeared. Deep sea sharks like the Goblin Shark or the Frilled Shark, originated during the Cretaceous Era. Cretaceous Period: Recognizable Sharksĭuring the Cretaceous Era, 145 to 65 million years ago, many of the sharks still alive today developed. One of the more unique evolutionary quirks of this era was the appearance were non-extinct horned sharks like the Hybodus. Sharks also evolved unique traits to respond to habitat pressures like bioluminesce among deep sea sharks. Most sharks also developed mouths under their snout. They also developed tail fins that allowed them to swim faster and more efficiently. During the Jurassic Era, sharks began to evolve flexible and protruding jaws so they could attack and eat larger prey. These sharks were the predecessors of the sharks that exist today. The Jurassic Era began around 200 million years ago, during this time 12 new families of sharks appeared. The Jurassic Era: The Rise of Modern Sharks This was the most diverse period of sharks in Earth’s history. During the Carboniferous Era, there were 45 different families of sharks not including rays. Strange species of sharks like the Stethacanthus, a shark like a flat anvil-like, spiky fin, the Eugeneodontida, a shark with a tooth whorl at the end of their bottom jaw, and the Falcatus, nickname the unicorn shark, grew a long, sharp horn on it’s head evolved during this period. Some of the most unique species of sharks that ever existed lived during this era. Sharks had incredibly diverse physiognomy during the Carboniferous age. Sharks also split into many subspecies including rays, skates, and chimaeras. It was during this time that sharks dominated the oceans. The Carboniferous Era began around 360 million years ago. The Carboniferous Era: The Golden Age Of Sharks ![]() The main differences between the Cladoselache and modern sharks are the round nose shape, lack of claspers, and its jaw was inflexible and fixed to its head. It was six feet long, with a streamlined body, 5-7 gill slits, and dorsal fins. The Cladoselache differed from its eel-like ancestors, because it’s body looked more like what a modern shark looks like. Late Devonian Era: The First Modern Sharkĭuring the late Devonian Era, the first shark in its modern incarnation appeared, the Cladoselache. ![]() Both of these species are considered to be in the now extinct early shark genus Xenacanthus. The Antarctilamna was also eel-like but had a small fin behind it’s head. Another freshwater shark discovered from this period was the Antarctilamna. However, the fossil remains of its two-pronged teeth lead scientists to believe that it was about 16 inches long, with an eel-like body and lived in freshwater. Very little is known about the Leonodus Shark. This is when the very first, fully developed shark, the Leonodus Shark, evolved. Early Devonian Era: Shark Evolution BeginsĪbout 50 millions years of after the SIlurian Era, the Devonian Era began. All sharks living today have evolved from this early fish. ![]() Acanthodians, also called “spiny sharks,” were the first fish to not only take on the physical characteristics of a shark, but to develop the cartilaginous skeletal structures that define sharks. One of these fish, the Acanthodian, was the very first ancestor of the modern shark. During that time, the ocean was filled with a variety of bony fish. The Future: Uncertainty The Silurian Era: The First SharksĤ50 million years ago, during the Silurian period, sharks first began developing as a unique species. ![]()
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